Tool for cutting materials and methods for sterilizing the same

ABSTRACT

A tool for cutting materials such as animal carcasses and portions of carcasses one after another, the tool including a cutting blade and a guard member, together with means for discharging against the blade and against the guard member hot water at sterilizing temperature for sterilizing the cutting blade and guard between their use in cutting different carcasses. The disclosure also deals with a process in which one carcass is cut using the tool, the tool withdrawn and the blade and guard then treated by discharging sterilizing water thereon before the tool is again used in the cutting of other carcasses.

This is a division of application Ser. No. 806,468 filed June 14, 1977which is in turn a division of Ser. No. 652,405 filed Jan. 26, 1976, nowabandoned.

This invention relates to a saw or cutting device or use on meatcarcasses or the like and to methods and apparatus for sterilizing thesame.

BACKGROUND

In meat packing houses where animal carcasses are cut into halves,quarters or other portions, it has been the practice to use portable,motorized saws to saw through the bone as well as the meat.

It is important in such operations, in the event one carcass becomescontaminated or infected, that such contamination or infection not betransferred to other carcasses on which the same saw is subsequentlyused; and to preclude such occurance it has been required that the sawbe sterilized by dipping it in hot water between carcasses. Pursuant tothis requirement the saw operator has followed the procedure of dippinghis saw in water having a temperature of at least 180° F. after he hasused the saw to sever each carcass and before he again uses the saw tosever another carcass. To do this, the operator must swing his saw aboutfrom his work and take the time and trouble to dip the saw in the hotwater and again swing it back into position hopefully before the nextcarcass comes to his position. Further, the hot water in which he dipshis saw receives debris from the saw, and even though the water be atsterilizing temperature the saw when it is dipped may come into contactwith the debris from prior carcasses.

We have sought methods for sanitizing the saws in such operations whichmethods are easier to perform and more effective for sanitizingpurposes, and we have sought apparatus for carrying out such improvedmethods.

Further, we recognize that for safety sake it is necessary that thecircular saw blades used for such purpose have suitable guards, and thatsuch guards must also be sterilized as well as the saw bladesthemselves.

DESCRIPTION

According to our improved method and apparatus, sterilizing water isprojected against the saw blade and guard member between the sawingoperations without need for the operator to maneuver his saw or move itfrom one position to another. One embodiment of apparatus for carryingout this procedure is illustrated in the accompanying drawings and isdescribed in detail herein.

In the drawings,

FIG. 1 is a view in side elevation showing one side of the saw and guardstructure;

FIG. 2 is a view of the other side of the saw and guard structure;

FIG. 3 is a view of the saw and guard structure as seen from the line3--3 of FIG. 1; and

FIG. 4 is an enlarged detail view showing the apparatus, partly insection, as seen from line 4--4 of FIG. 1.

As illustrated, the apparatus includes a circular cutting blade 10 whichis rotatably driven by a motor 11 through a shaft 12 and gearingmechanism 13.

The motor is connected to an electrical power source by cable 14. Ahandle 15 is provided at the end of the motor. The shaft 11 is protectedby casing 16, and a handle 17 is attached to the shaft casing. Thisprovides a tool which is portable. The operator may grasp the handle 15with one hand and the handle 17 with the other hand and so move theblade into contact with an animal carcass while the carcass is suspendedon a moving conveyor so as to cut the carcass as it passes by on theconveyor.

The cutting blade 10 is circular and has a cutting edge at itsperiphery. Preferably this cutting edge is that of a saw having teeth18, but the tool could also be used with a blade having a plain knifeedge or a serrated edge.

Cutting blade 10 is protected by a guard 20 which is an angle pieceincluding an arcuate band 21 which extends about and is spaced from thecutting blade. This band 21 extends part way about the cutting blade andis concentric with the blade. As shown more clearly in FIG. 3 this band21 has a boss 22 on its inside which extends about the casing 16 and issecured to a connecting plate 23a which is, in turn, secured to thecasing. The guard is thus held in place with the band 21 uniformlyspaced from the edge of the blade.

A vertical plate 24 is joined at right angles with the band 21 (SeeFIGS. 1 and 4) and serves to protect the front side of the cuttingblade.

A casing 25 is attached to the band 21 and this casing is connected bythe tube 26 with a source of hot water under pressure. A valve (notshown) is connected in the hot water line and some means is provided forcontrolling the flow of the water into the casing. Preferably, suchcontrol takes the form of a foot pedal which the operator of the toolmay operate with his foot to turn on and off the flow of hot water intothe casing 25.

An opening 27 is provided through the bottom of casing 25 and throughthe guard band 21, through which water from casing 25 is discharged ontothe cutting blade. The opening 27 provides structure which guides anddirects the water in the nature of a nozzle as it is discharged againstthe cutting blade. The opening and the nozzle which it provides isaligned with the plane of the cutting blade so that the water issuingfrom this nozzle in the form of a stream or spray is directed againstthe edge of the blade and contacts the blade on both sides. In this waythe entire surface of the blade is contacted by the water. We use theterm "protected" to include putting the hot water against the blade orthe guard in the form of a stream or spray in contrast to the immersionof the device according to prior practice. In accordance with ourmethods the blade may continue to rotate as the water is dischargedthrough the opening against it.

The improved device also includes a tube 30 made of aluminum or othermetal or plastic material which is in the form of an arc and which isconcentric with the guard band 21 and is secured to band 21 by means ofbracket 31. Tube 30 is spaced from band 21 and is positioned just overthe front edge portion of band 21 where it is substantially in alignmentwith the guard plate 24. Tube 30 is open to the interior of casing 25and water is received from the interior of casing 25 into the tube 30.

Tube 30 is provided with spaced perforations along its length and in itsinside wall, the inside wall being the side of the tube facing theguard. These perforations have a radial direction with respect to thetube so that some of the perforations direct water straight against theguard, some of them direct water against the guard in directions slantedtoward one side and some of them direct water against the guard slantedtoward the other side. Thus, the water so discharged covers the entirearea of the guard band 21 and also the guard plate 24. In this way boththe blade and the guard are sterilized. Suitably, the operator mayrelease his foot control to stop the flow of sterilizing water after theflow has continued for a short period, because the flow of water is notneeded after sterilization has taken place. After the flow has stoppedhe may then press the cutting blade against the next carcass which comesby his station on the conveyor. By this sequence of steps the carcassesmay be cut one after another and both the cutting blade and the guardare sterilized between carcasses. This relieves the operator fromturning his tool from his work and dipping it in hot water as was theprior practice. Also it enables more positive and complete sterilizationwith clean water without danger of contamination between carcasses andwithout contact with debris from prior usage.

Further, the prior practice of dipping the blade and associatedequipment into hot water between use on the different carcasses tends todeteriorate the gearing mechanism rapidly, and this deterioration islargely avoided by use of the improved tool as herein described.

While we have illustrated and described only certain embodiments of ourinvention, it will be understood to those skilled in this art that manyembodiments may be constructed and utilized and many changes may be madeall within the spirit of the invention and the scope of the appendedclaims.

We claim:
 1. A portable cutting tool comprising a circular disc-likeblade having a cutting edge at its periphery, means for rotating saidblade, a guard which includes an arcuate band extending about and spacedfrom said edge of the blade, a casing attached to the exterior of saidband, a source of water under pressure having sterilizing temperature,tube means for conducting water from said source to the interior of saidcasing, an opening leading from the interior of said casing and throughsaid band, said opening being aligned with the plane of said bladewhereby water projected under pressure through said opening is caused tostrike the edge of said blade, and conduit means connected with saidcasing for delivering sterilizing water from said casing to the exteriorside of said band, said conduit means including a tube in arcuate formand having perforations therein which face the exterior of said band. 2.A cutting tool as set forth in claim 1 including a plate which is joinedat right angles with said band and which extends on the front side ofsaid blade and in which some of said perforations in said tube means aredirected toward said plate.
 3. A portable cutting tool comprising acircular disc-like blade having a cutting edge at its periphery, meansfor rotating said blade, a guard which includes an arcuate bandextending about and spaced from said edge of the blade, a source ofwater under pressure having sterilizing temperature, an arcuate tube onthe outside of and spaced from said band, said tube having perforationson the inside wall thereof and facing said band, and a conduit means forconnecting said source to said tube for passing sterilizing water underpressure from said source to said tube to thereby cause said water topass through said tube and the perforations thereof and against theoutside of said band.